I am going from a 12 sho 250 to a 23 proxs 250 and was told i would be disappointed by the loss i will see in performance by a very experienced engine/prop specialist. Has anyone experienced this? Thanks
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I am going from a 12 sho 250 to a 23 proxs 250 and was told i would be disappointed by the loss i will see in performance by a very experienced engine/prop specialist. Has anyone experienced this? Thanks
I can't speak on that, but I've got a buddy with a back country 201 with a newish 250 PRO XS......his boat is fast.......faster than mine and I have the same hull, a little different cap and 300R.......I picked up 13 mph going from a 250 SHO to a 300R on a Lake + Bay backwater. The 300R has a lot more torque and better fuel economy also.
Get it set up correctly I don't think you will be disappointed!
4 stroke technology is here to stay. We will always have naysayers when older technology is replaced.
^ This
I admit I'm a 250 sho owner but I've had Mercs and love them as well. One thing that I just can't wrap my head around is this: If HP is HP and 250HP Yamaha SHO = 250HP Merc ProXs (non racing) then why do so many people have to drop several pitches in prop to run the new Merc? To me having to drop in pitch says the engine doesn't have the needed torque to run the higher pitch prop or at least the engine doesn't have the low end grunt. My FX21 jumps on plane with a 25P Yamaha T1 prop. I see were many people with similar hulls as mine (non go-fast hulls like Bullet, Stroker) have to drop to 23P or some even report 22P. I have a hard time understanding this. Some will say that the Merc has a higher WOT rpm than the SHO so the lower pitch prop is needed but again power should be power and if you have 250HP available and the lower unit gear ratios are the same then why the need to drop so much in prop pitch? Someone educate me. I'm really wanting to understand the science of this. Not bashing the Merc 4 strokes at all.
A lot of this has to do with the gearing of the LU and the WOT RPM. Each motor is different. For example, I have owned 150 Optimax motors. One had a LU of 2.00 gears and the other 1.87. The 2.0 needed a 25 Tempest and the 1.87 needed a 23 Tempest. Unless everything is the same, you really cannot compare props.
You're not going to have the same hp on a stock merc 250 vs your flashed SHO, but you should be able to run 22 or 23 Fury at 2000 feet. I went from a stock 250 Sho to a new ProXS 250 and haven't been disappointed on a BassCat. I'm running a 23 Fury at 2400 feet altitude on a Cougar.
Yes a 4 stroke 250 PRO XS. The PRO XS's have A LOT more torque than the 2 strokes. They like bigger diameter props.......Mine is 2+ mph faster with a bravo XS over a pro max....... The Mercury's have a lot more balls than the SHO's.......I had an SHO and it felt anemic in comparison.
The newer merc lower units have alot less slip than the old ones. This allows for a smaller pitch prop to achieve the same speed at the same rpm as a bigger prop with more slip. Also allows for better holeshot with a smaller pitch, and as stated, a 6200 rpm max on the merc. The fury prop that most are running also is a bit stiff, a 24 is more like a 25 etc
I have had four. The first one seemed good. The rest have all felt weak.